Viralytics (VLA) In one of the most spectacular small-cap rallies on Wednesday, shares in the biotech minnow shot up as much as 42 per cent after it won a US patent for its lead cancer-fighting Cavatak product, currently at clinical testing stage. The patent's scope gives the group intellectual property rights for its family of four cancer-fighting viruses, which have been effective in treating a variety of cancers bearing the ICAM-1 molecule. The patent gives Viralytics rights over the viruses, known as the Coxsackie A-group viruses, until 2022, with the option of a five-year extension. Smaller biotech stocks typically have large price spikes around key regulatory milestones and the Viralytics share price began to run late last week. By the close of trade on Wednesday it had gained more than 60 per cent in 5 sessions. Shares were 1.4¢ higher at 8¢ at 4pm AEST on Wednesday. Cluff Resources Pacific NL (CFR) The generally illiquid shares in junior explorer Cluff sprang to life on Wednesday after it said it had uncovered healthy grades of silver and tin at its Buddigower mine in central NSW. Shares shot up 37.5 per cent to 1.1¢ on a massive spike in traded volume - the largest volume increase of any stock on the market on Wednesday - after the miner said drill holes had revealed an extensive resource of both silver and tin. Geologists will now rework original estimates of contained silver, gold and tin at the open-pit site. In addition to tin and silver, the explorer is searching for diamonds, rubies and sapphires at sites in northern NSW and Queensland. FlexiGroup (FXL) The nine-month-long collapse in FlexiGroup's share price got a day of reprieve on Wednesday as the stock rallied 5.9 per cent to 62.5¢ to end a four-session losing streak. Having scraped a fresh low of 47.5¢ just three weeks ago, FlexiGroup shares are now trading on a fiscal 2009 earnings multiple of 4 times and is "priced for disaster", according to UBS analysts. The share price rout seems to endorse the UBS view that macro-economic headwinds have only intensified for FlexiGroup's business since the start of the year. As a provider of lease and rental financing for a range of whitegoods, IT products and other electrical and audio-visual equipment, the company has been hit hard by fears about consumer spending and a tough competitive environment. Peers such as Grenkeleasing and ThinkSmart were trading on consensus 2009 earnings multiples of 9.6 times and 12.2 times respectively, UBS said. It maintained its "buy" rating on the stock, saying recent director buying also provided some confidence.